To get Extra Speed in races you need to turn of the Traction Control. This will help in the Time Lapped races.
If your Tv is in 1080i then your side mirrors are more likely to lose some quality!!
Complete all main A, B and C Classes with at least Bronze Medal or better
Unlock BMW Concept 1 Series tii '07 Beat all Class B Races
Unlock Daihatsu OFC-1 Beat all Class C Races
Unlock Nissan GT-R Proto '05 Beat all Class S Races
Unlock Nissan Skyline Coupe Concept 'p7 Beat all Class A Races
When about to start a race go to adjust and (if available:) set weight of car to minimal and hp of car to maximal.
(Not sure works on online game.)